1. Field of the Invention
This invention relates to a bracket assembly for supporting terminal block means on a circuit breaker and a related method for securing the bracket assembly to the circuit breaker.
2. Background Information
Terminal blocks are mounted on the outside of a circuit breaker and are electrically connected to the circuit breaker by wires which are drawn through horizontal slots in the circuit breaker housing. Terminal blocks are generally connected to auxiliary contact devices such as a bell switch which is used to provide an indication of a tripped condition of the circuit breaker, or connected to a printed circuit board, for remote communications on the functions that the PCB is performing. One arrangement for securing the terminal block to the outside of a circuit breaker consists of a terminal block which has two T-shaped members on its rear wall, each of which fit and slide into a vertical slot on a sidewall of the housing.
Since only two slots are provided on the sidewall of the circuit breaker housing, only one terminal block can be used in conjunction such a circuit breaker. If additional terminal blocks are required, then additional slots need to be provided in the sidewall of the housing, although they would unacceptably weaken the housing. For a particular application, it is apparent that this arrangement has limitations in that the number of slots dictate the number of terminal blocks which can be supported by the circuit breaker.
In order to expand the capacity for supporting a number of terminal blocks, a long bracket has been provided in some installations whereby several terminal blocks are secured to the bracket. A problem with this type of arrangement is that the bracket is unstable or wobbly and cannot be fixedly secured to the circuit breaker housing. A further problem with this arrangement is that since the bracket is mounted flush against the housing, plastic screws are needed to maintain electrical isolation between the inside of the housing which contains the circuit breaker mechanism and the outside of the housing. However, the walls of the housing are generally thin and of poor material for tapping. Thus, plastic screws are not a satisfactory solution. Heavy duty double stick tape has been suggested, but it also does not adequately secure the bracket to the molded housing.
There remains, therefore, a need for a circuit breaker to accommodate several terminal block assemblies alongside its outer housing wall on a bracket assembly which is fixedly secured to the circuit breaker housing and which is electrically isolated from the circuit breaker mechanism.